The present invention relates to the fusion of multi-modal medical images, and more particularly, to model based fusion of pre-operative computed tomography (CT) and intra-operative fluoroscopic images using Transesophageal Echocardiography (TEE).
In current clinical practice, minimally invasive percutaneous cardiac interventions, such as Transcatheter Aortic Valve Implantation (TAVI), are becoming more prevalent as compared with traditional open heart surgical procedures. Such minimally invasive percutaneous cardiac interventions have advantages of shorter patient recovery times, as well as faster and less risky procedures that d not require anesthesia. In such minimally invasive cardiac interventions, devices such as implants are delivered into the patient through vessels via a catheter. Navigating the catheter inside the vessels of a patient is challenging. X-ray fluoroscopy is typically used to visualize the catheter; however, this imaging modality does not capture soft tissue structure of the patient well. A contrast medium can be injected periodically through the catheter to enhance the fluoroscopy image and enable the view of the vessel and surrounding tissue. In addition, a second imaging modality, such as Transesophageal Echocardiography (TEE), is often used in the operating room in order to visualize soft tissue. However, TEE has a small field of view and thus can only display a limited context of the soft tissue.
Visualization of the catheter and the surrounding soft tissue typically requires two display in the operating room, one showing the TEE and the other showing the fluoroscopy image. The surgeon must interpret the two separately displayed imaging modalities, extract relevant information, and spatially transform the information between the two coordinate systems and ultimately into the patient.